char intext[] = "The problem will be solved until12345"; = 37 !!
It's very strange for me!
Thanks,
Rafael
Dr. Stephen Henson wrote:
On Mon, Mar 21, 2005, Rafael Cividanes wrote:
I'm doing a little program to encrypt and decrypt a string using the EVP API. I couldn't understand if I have to use EVP_DecryptFinal_ex( ) or just EVP_DecryptUpdate( ) in the decryption operation. The second function return the entire recovered plaintext, then I can't understand why EVP_DecryptFinal_ex( ) exist. Just for checking error?
Here is my code:
int main(int argc, char *argv[])
{
EVP_CIPHER_CTX ctx;
char key[EVP_MAX_KEY_LENGTH];
char iv[EVP_MAX_IV_LENGTH];
char intext[] = "The problem will be solved until12345"; //32
In that example you'll be able to receive all the data because EVP_DecryptFinal_ex() wont have a partial final block to recover. The reason is that the plaintext is a multiple of the block length (16 for AES).
If you try it with plaintext that isn't an exact multiple of the block size you'll see the difference.
Steve. -- Dr Stephen N. Henson. Email, S/MIME and PGP keys: see homepage OpenSSL project core developer and freelance consultant. Funding needed! Details on homepage. Homepage: http://www.drh-consultancy.demon.co.uk ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager [EMAIL PROTECTED]
-- Rafael Cividanes Instituto Tecnológico de Aeronáutica - ITA Divisão de Ciência da Computação - IEC Pça. Mal.Eduardo Gomes, 50 Vila das Acácias CTA-ITA-IEP 12.228-900 São José dos Campos,SP Prédio da Guerra Eletrônica - Sala 235 Tel 12-39476891 E-mail: [EMAIL PROTECTED]
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